The present invention relates to a system for facilitating and improving the procedure for selecting the proper color for artificial teeth in the creation of life-like teeth replacement and bridgework.
The creation of false teeth and bridges is no longer a major engineering or physical task for the dentist, prosthodontist or even the technician, (hereinafter simply referred to as the dentist) since the advent of plastic teeth and bridge supports have allowed the almost precise reconstruction of the gum and teeth configurations. On the other hand, a considerable proportion of the time and cost for reconstructing a patient's mouth is spent on the aesthetics involved therein, and in particular, in determining the proper color, shade, and other characteristics of the artificial teeth in order that the new teeth match closely with the original as well as to provide a most natural appearance for the wearer.
A dentist must initially prepare the patient's mouth, in order to fabricate dental appliances, (commonly called dentures), such as partials, crowns, bridges, veneers, laminates, over dentures, implants (an implant to be finished needs the reconstruction of false teeth and supporting structure). After the preparation has been done, an impression is usually obtained. At this point, it is necessary for the dentist to decide on the shade/color of any replacement of the teeth. This procedure is normally done by using a shade guide such as that shown in FIG. 1. Shade guides are made by manufacturers of prefabricated teeth for use as dentures, partials and implant over dentures. Crowns, bridges, laminates and veneers are, on the other hand, generally manufactured by dental laboratories using tooth powder materials (resins or porcelain) which have also been manufactured by tooth manufacturers.
The conventional shade guide has an average of 12 shade selections fixedly mounted in sequence on a common holder. The dentist must match one of these shades to the existing teeth in the patient's mouth. If the patient is edentulous, then the dentist will select a shade according to the age of the patient based on his experience. When the selection is made, the doctor must write down the shade number (and/or brand of teeth or material) on a prescription. The prescription, plus the impression (usually made of silicone, alginate or rubber base) are sent to a laboratory where the appliance is fabricated. The laboratory set-up man or master technician will have to select the teeth (for dentures, partials or implant over dentures) or the tooth materials (for crowns, bridges, laminates or veneers) matching the shade number given by the doctor in the prescription.
Most of the time this procedure does not guarantee a perfect match because of many factors:
1. The shade guide in the hands of the doctor is not the same as the one in the hands of the lab. PA1 2. The shade guide in the hands of the doctor was purchased many years previously while the shade guide and/or inventory of teeth and tooth materials, in the hands of the technician are of recent manufacture or different batches and different aging. PA1 3. The doctor misread the color number on the shade guide or did not match the shade correctly. PA1 4. The doctor's shade guide was overexposed to sunlight or it was constantly disinfected or sterilized modifying the original tones. PA1 5. The technician is constructing an appliance without having a good idea of the patient's shade because he/she has not seen the patient. (The most sophisticated and experienced doctors send their patients to see their lab master technicians to verify the shades). PA1 6. The manufacturer made a mistake and the shade in the guide is not identified correctly. PA1 7. The manufacturer slightly changed the shades in its production batches of teeth or tooth powder because of forced changes of one ingredient.
In these cases, the dentist will send back the appliance because the shade does not match and this problem cannot be fixed at chairside. While most of the mechanical problems can be fixed at chairside, these recurring problems of shade matching can not and result in loss of labor time.
It is the prime object of the present invention to overcome the difficulties and disadvantages of the prior devices and to avoid additional loss of time, money and terrible inconvenience for the patient.
It is the object of this invention to provide a more precise method of selecting the shade of teeth and tooth material according to our actual physical reference.
Artificial teeth, and materials to custom make them, are manufactured by several companies and facilities throughout the world. The dentist is nevertheless capable of making the selection from any one of a number of these manufacturers and suppliers.
The foregoing objects, as well as others, will be apparent from the following disclosure of the present invention.